1. Field of the Invention
The present invention relates to an apparatus for controlling the movement of a graphical element on a computer display monitor that is engaged with a keyboard assembly and provides improved control over movement of the graphical element.
2. Description of the Related Art
Current computer keyboards, especially those provided with a laptop computer, sometimes include a pointing device embedded between the keys of the keyboard. This pointing device typically looks and feels like an eraser. FIG. 1 illustrates this eraser style pointing device 2 embedded between keyboard keys 4. FIG. 1 also shows lateral views, referenced as 6a and 6b, of the eraser-style pointing device with respect to the keyboard keys. The user may control the eraser pointing device 2 with a fingertip, usually the forefinger, to move the eraser pointing device in directions along the X-Y plane to control the movement of a cursor or other graphical element displayed in a graphical user interface (GUI) on a computer display monitor. The eraser pointing device 2 remains relatively stationary when the user applies pressure in different directions. One example of the eraser pointing device is the International Business Machine Corporation ("IBM") TrackPoint in-keyboard pointing device.
Such eraser pointing devices 2 are particularly advantageous because they fit into a laptop computer keyboard and provide the user mouse-like control within the keyboard area. In the prior art, the height of such eraser pointing devices 2 extends to the height of the keys on the keyboard or only very slightly above the keys, such as by an eighth of an inch or less. Prior art eraser pointing devices 2 are shaped as a button as shown in FIG. 1. The height and shape of the eraser type pointer device is designed to insure that the eraser pointing device 2 will not puncture or damage the LCD display screen of a laptop computer when the display screen cover is shut closed and positioned flush with the keyboard and eraser pointing device 2. Examples of eraser pointing devices such as the device shown in FIG. 1 are described in the following U.S. patents, all of which are incorporated herein by reference in their entirety: U.S. Pat. No. 5,701,142, entitled "Pointing Stick with Tripod Actuator for Cursor Control in a Computer Keyboard;" U.S. Pat. No. 5,568,987, entitled "Pointing Stick in a Computer Keyboard for Cursor Control;" and the commonly assigned U.S. Pat. No. 5,870,082, entitled "Pointing Device With Reciprocating Grip Cap."
One problem with the current eraser style pointing devices is that users have limited control over movement in the X-Y plane. This limitation in movement is especially problematic when playing computer video games. Computer games such as flight simulators and other action games typically require quick, accurate user movements. The eraser style pointing devices do not provide the user the desired level of control over cursor or game element movement in the X-Y plane to adequately interact in the computer gaming environment.
There is thus a need in the art for a pointing device suitable for being embedded in a keyboard and particularly suited for laptop use to provide users greater control over the movement of cursors and other displayed graphical elements.